1. Field
Embodiments relate to a robot cleaning device including a debris detecting unit, and more particularly, to a robot cleaning device including a debris detecting unit having improved debris detecting performance.
2. Description of the Related Art
An autonomous robot is a device for performing a desired task while traveling about a certain region without being operated by a user. Such a robot may substantially operate autonomously. Autonomous operation may be achieved in various manners. For example, the robot may travel about a certain region along a predetermined path or may travel about a certain region under the condition that there is no predetermined path of the robot.
A robot cleaning device is a device for cleaning a floor in a cleaning region while traveling about the cleaning region without being operated by a user. In detail, such a robot cleaning device may perform a vacuum cleaning operation and a wiping operation in a home. Here, debris may mean (soil) dust, mote, powder, scrap, and other dust particles, which may be collected by a vacuum cleaner or an automatic or semi-automatic cleaning device.
Conventional robot cleaning devices detect debris on a floor in a cleaning region when cleaning the floor while travelling about the cleaning region, in order to concentratedly or repeatedly clean an area where debris is detected. Also, conventional robot cleaning devices include a debris amount detecting unit installed in a debris box while including a light emitter and a light receiver. As debris is accumulated in the debris box, light to be transmitted to the light receiver may be shielded. This shielding is detected to identify the amount of the accumulated debris.
Of course, in a conventional robot cleaning device (disclosed in, for example, Korean Unexamined Patent Publication No. 10-2005-0073082), several sensors or several kinds of sensors are installed to detect introduction of debris from a floor into a debris box, and to detect the amount of debris in the debris box. In this case, there is a problem in that too many sensors are unnecessarily installed, so that an increase in manufacturing costs may occur or the sensors may occupy a large space in the interior of the robot cleaning device.
The above-mentioned conventional robot cleaning device also has a problem in that, even when one or more sensors malfunction during a cleaning operation, the cleaning operation may be continuously carried out without necessary measures, except for issuing an alarm to the user, or may be completely stopped.
Also, conventional robot cleaning devices, which include debris sensors as mentioned above, perform a cleaning task based on a predetermined single reference value, without reflecting the cleaning task environment varying the kind of debris or the amount of debris. For this reason, it may be difficult for such conventional robot cleaning devices to achieve effective cleaning.